Can You Eat Too Much Fruit?

Can You Eat Too Much Fruit?.jpeg

In my video If Fructose is Bad, What About Fruit?, I explored how adding berries to our meals can actually blunt the detrimental effects of high glycemic foods, but how many berries? The purpose of one study out of Finland was to determine the minimum level of blueberry consumption at which a consumer may realistically expect to receive antioxidant benefits after eating blueberries with a sugary breakfast cereal. If we eat a bowl of corn flakes with no berries, within two hours, so many free radicals are created that it puts us into oxidative debt. The antioxidant power of our bloodstream drops below where we started from before breakfast, as the antioxidants in our bodies get used up dealing with such a crappy breakfast. As you can see in How Much Fruit is Too Much? video, a quarter cup of blueberries didn't seem to help much, but a half cup of blueberries did.

What about fruit for diabetics? Most guidelines recommend eating a diet with a high intake of fiber-rich food, including fruit, because they're so healthy--antioxidants, anti-inflammatory, improving artery function, and reducing cancer risk. However, some health professionals have concerns about the sugar content of fruit and therefore recommend restricting the fruit intake. So let's put it to the test! In a study from Denmark, diabetics were randomized into two groups: one told to eat at least two pieces of fruit a day, and the other told at most, two fruits a day. The reduce fruit group indeed reduce their fruit consumption, but it had no effect on the control of their diabetes or weight, and so, the researchers concluded, the intake of fruit should not be restricted in patients with type 2 diabetes. An emerging literature has shown that low-dose fructose may actually benefit blood sugar control. Having a piece of fruit with each meal would be expected to lower, not raise the blood sugar response.

The threshold for toxicity of fructose may be around 50 grams. The problem is that's the current average adult fructose consumption. So, the levels of half of all adults are likely above the threshold for fructose toxicity, and adolescents currently average 75. Is that limit for added sugars or for all fructose? If we don't want more than 50 and there's about ten in a piece of fruit, should we not eat more than five fruit a day? Quoting from the Harvard Health Letter, "the nutritional problems of fructose and sugar come when they are added to foods. Fruit, on the other hand, is beneficial in almost any amount." What do they mean almost? Can we eat ten fruit a day? How about twenty fruit a day?

It's actually been put to the test.

Seventeen people were made to eat 20 servings a day of fruit. Despite the extraordinarily high fructose content of this diet, presumably about 200 g/d--eight cans of soda worth, the investigators reported no adverse effects (and possible benefit actually) for body weight, blood pressure, and insulin and lipid levels after three to six months. More recently, Jenkins and colleagues put people on about a 20 servings of fruit a day diet for a few weeks and found no adverse effects on weight or blood pressure or triglycerides, and an astounding 38 point drop in LDL cholesterol.

There was one side effect, though. Given the 44 servings of vegetables they had on top of all that fruit, they recorded the largest bowl movements apparently ever documented in a dietary intervention.


Cutting down on sugary foods may be easier said than done (see Are Sugary Foods Addictive?) but it's worth it. For more on the dangers of high levels of fructose in added sugars, see How Much Added Sugar Is Too Much?.

What's that about being in oxidative debt? See my three part series on how to pull yourself out of the red:

Ironically, fat may be more of a problem when it comes to diabetes than sugar, see:

In health,
Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Can You Eat Too Much Fruit?

Can You Eat Too Much Fruit?.jpeg

In my video If Fructose is Bad, What About Fruit?, I explored how adding berries to our meals can actually blunt the detrimental effects of high glycemic foods, but how many berries? The purpose of one study out of Finland was to determine the minimum level of blueberry consumption at which a consumer may realistically expect to receive antioxidant benefits after eating blueberries with a sugary breakfast cereal. If we eat a bowl of corn flakes with no berries, within two hours, so many free radicals are created that it puts us into oxidative debt. The antioxidant power of our bloodstream drops below where we started from before breakfast, as the antioxidants in our bodies get used up dealing with such a crappy breakfast. As you can see in How Much Fruit is Too Much? video, a quarter cup of blueberries didn't seem to help much, but a half cup of blueberries did.

What about fruit for diabetics? Most guidelines recommend eating a diet with a high intake of fiber-rich food, including fruit, because they're so healthy--antioxidants, anti-inflammatory, improving artery function, and reducing cancer risk. However, some health professionals have concerns about the sugar content of fruit and therefore recommend restricting the fruit intake. So let's put it to the test! In a study from Denmark, diabetics were randomized into two groups: one told to eat at least two pieces of fruit a day, and the other told at most, two fruits a day. The reduce fruit group indeed reduce their fruit consumption, but it had no effect on the control of their diabetes or weight, and so, the researchers concluded, the intake of fruit should not be restricted in patients with type 2 diabetes. An emerging literature has shown that low-dose fructose may actually benefit blood sugar control. Having a piece of fruit with each meal would be expected to lower, not raise the blood sugar response.

The threshold for toxicity of fructose may be around 50 grams. The problem is that's the current average adult fructose consumption. So, the levels of half of all adults are likely above the threshold for fructose toxicity, and adolescents currently average 75. Is that limit for added sugars or for all fructose? If we don't want more than 50 and there's about ten in a piece of fruit, should we not eat more than five fruit a day? Quoting from the Harvard Health Letter, "the nutritional problems of fructose and sugar come when they are added to foods. Fruit, on the other hand, is beneficial in almost any amount." What do they mean almost? Can we eat ten fruit a day? How about twenty fruit a day?

It's actually been put to the test.

Seventeen people were made to eat 20 servings a day of fruit. Despite the extraordinarily high fructose content of this diet, presumably about 200 g/d--eight cans of soda worth, the investigators reported no adverse effects (and possible benefit actually) for body weight, blood pressure, and insulin and lipid levels after three to six months. More recently, Jenkins and colleagues put people on about a 20 servings of fruit a day diet for a few weeks and found no adverse effects on weight or blood pressure or triglycerides, and an astounding 38 point drop in LDL cholesterol.

There was one side effect, though. Given the 44 servings of vegetables they had on top of all that fruit, they recorded the largest bowl movements apparently ever documented in a dietary intervention.


Cutting down on sugary foods may be easier said than done (see Are Sugary Foods Addictive?) but it's worth it. For more on the dangers of high levels of fructose in added sugars, see How Much Added Sugar Is Too Much?.

What's that about being in oxidative debt? See my three part series on how to pull yourself out of the red:

Ironically, fat may be more of a problem when it comes to diabetes than sugar, see:

In health,
Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Benefits of Oatmeal for Fatty Liver Disease

Benefits of Oatmeal for Fatty Liver Disease.jpeg

If oatmeal is so powerful that it can clear up some of the ravages of chemotherapy just applied to the skin (see my video Oatmeal Lotion for Chemotherapy-Induced Rash), what might it do if we actually ate it? Oats are reported to possess varied drug-like activities like lowering blood cholesterol and blood sugar, boosting our immune system, anticancer, antioxidant, and anti-atherosclerosis activites, in addition to being a topical anti-inflammatory, and reprtedly may also be useful in controlling childhood asthma and body weight.

Whole-grain intake in general is associated with lower risk of type 2 diabetes, cardiovascular disease, and weight gain, as shown in my video Can Oatmeal Help Fatty Liver Disease?. All of the cohort studies on type 2 diabetes and heart disease show whole grain intake is associated with lower risk.

Researchers have observed the same for obesity--consistently less weight gain for those who consumed a few servings of whole grains every day. All the forward-looking population studies demonstrate that a higher intake of whole grains is associated with lower body mass index and body weight gain. However, these results do not clarify whether whole grain consumption is simply a marker of a healthier lifestyle or a factor favoring lower body weight.

For example, high whole grain consumers--those who eat whole wheat, brown rice, and oatmeal for breakfast--tend to be more physically active, smoke less, and consume more fruit, vegetables, and dietary fiber than those that instead reach for fruit loops. Statistically, one can control these factors, effectively comparing nonsmokers to nonsmokers with similar exercise and diet as most of the studies did, and they still found whole grains to be protective via a variety of mechanisms.

For example, in terms of helping with weight control, the soluble fiber of oatmeal forms a gel in the stomach, delaying stomach emptying, making one feel full for a longer period. It seems plausible that whole grain intake does indeed offer direct benefits, but only results of randomized controlled intervention studies can provide direct evidence of cause and effect. In other words, the evidence is clear that oatmeal consumers have lower rates of disease, but that's not the same as proving that if we start eating more oatmeal, our risk will drop. To know that, we need an interventional trial, ideally a blinded study where you give half the people oatmeal, and the other half fake placebo oatmeal that looks and tastes like oatmeal, to see if it actually works. And that's what we finally got--a double-blinded randomized trial of overweight and obese men and women. Almost 90% of the real oatmeal-treated subjects had reduced body weight, compared to no weight loss in the control group. They saw a slimmer waist on average, a 20 point drop in cholesterol, and an improvement in liver function.

Nonalcoholic fatty liver disease, meaning a fatty liver caused by excess food rather than excess drink, is now the most common cause of liver disease in the United States, and can lead in rare cases to cirrhosis of the liver, cancer of the liver, and death. Theoretically, whole grains could help prevent and treat fatty liver disease, but this is the first time it had been put to the test. A follow-up study in 2014 confirmed these findings of a protective role of whole grains, but refined grains was associated with increased risk. So one would not expect to get such wonderful results from wonder bread.

How can you make your oatmeal even healthier? See Antioxidants in a Pinch.

Whole Grains May Work As Well As Drugs for hypertension, but refined grain intake may linked with high blood pressure and diseases like diabetes. But If White Rice is Linked to Diabetes, What About China?.

More on keeping the liver healthy in videos like:

In health,
Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Benefits of Oatmeal for Fatty Liver Disease

Benefits of Oatmeal for Fatty Liver Disease.jpeg

If oatmeal is so powerful that it can clear up some of the ravages of chemotherapy just applied to the skin (see my video Oatmeal Lotion for Chemotherapy-Induced Rash), what might it do if we actually ate it? Oats are reported to possess varied drug-like activities like lowering blood cholesterol and blood sugar, boosting our immune system, anticancer, antioxidant, and anti-atherosclerosis activites, in addition to being a topical anti-inflammatory, and reprtedly may also be useful in controlling childhood asthma and body weight.

Whole-grain intake in general is associated with lower risk of type 2 diabetes, cardiovascular disease, and weight gain, as shown in my video Can Oatmeal Help Fatty Liver Disease?. All of the cohort studies on type 2 diabetes and heart disease show whole grain intake is associated with lower risk.

Researchers have observed the same for obesity--consistently less weight gain for those who consumed a few servings of whole grains every day. All the forward-looking population studies demonstrate that a higher intake of whole grains is associated with lower body mass index and body weight gain. However, these results do not clarify whether whole grain consumption is simply a marker of a healthier lifestyle or a factor favoring lower body weight.

For example, high whole grain consumers--those who eat whole wheat, brown rice, and oatmeal for breakfast--tend to be more physically active, smoke less, and consume more fruit, vegetables, and dietary fiber than those that instead reach for fruit loops. Statistically, one can control these factors, effectively comparing nonsmokers to nonsmokers with similar exercise and diet as most of the studies did, and they still found whole grains to be protective via a variety of mechanisms.

For example, in terms of helping with weight control, the soluble fiber of oatmeal forms a gel in the stomach, delaying stomach emptying, making one feel full for a longer period. It seems plausible that whole grain intake does indeed offer direct benefits, but only results of randomized controlled intervention studies can provide direct evidence of cause and effect. In other words, the evidence is clear that oatmeal consumers have lower rates of disease, but that's not the same as proving that if we start eating more oatmeal, our risk will drop. To know that, we need an interventional trial, ideally a blinded study where you give half the people oatmeal, and the other half fake placebo oatmeal that looks and tastes like oatmeal, to see if it actually works. And that's what we finally got--a double-blinded randomized trial of overweight and obese men and women. Almost 90% of the real oatmeal-treated subjects had reduced body weight, compared to no weight loss in the control group. They saw a slimmer waist on average, a 20 point drop in cholesterol, and an improvement in liver function.

Nonalcoholic fatty liver disease, meaning a fatty liver caused by excess food rather than excess drink, is now the most common cause of liver disease in the United States, and can lead in rare cases to cirrhosis of the liver, cancer of the liver, and death. Theoretically, whole grains could help prevent and treat fatty liver disease, but this is the first time it had been put to the test. A follow-up study in 2014 confirmed these findings of a protective role of whole grains, but refined grains was associated with increased risk. So one would not expect to get such wonderful results from wonder bread.

How can you make your oatmeal even healthier? See Antioxidants in a Pinch.

Whole Grains May Work As Well As Drugs for hypertension, but refined grain intake may linked with high blood pressure and diseases like diabetes. But If White Rice is Linked to Diabetes, What About China?.

More on keeping the liver healthy in videos like:

In health,
Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link